Related papers: Central UV Spikes in two Galactic Spheroids

Recently Sahu et al., using the Hubble Space Telescope to monitor stars in the direction of the old globular cluster M22, detected six events in which otherwise constant stars brightened by ~50% during a time of <1 day. They tentatively…

This work reports the detection of a multi peaked colour pattern in the integrated colours distribution of globular clusters associated to the giant elliptical galaxy NGC 4486, using Next Generation Virgo Survey data. This feature is…

The discovery over the last several decades of moderate luminosity AGNs in disk-dominated galaxies - which show no "classical" bulges - suggests that secular mechanisms represent an important growth pathway for supermassive black holes in…

The enigma source, RX J1856.5-3754, is one of the so-called dim thermal neutron stars. Two puzzles of RXJ1856.5-3754 exist: (1) the observational X-ray spectrum is completely featureless; (2) the UV-optical intensity is about seven times…

We present V-band surface photometry and major-axis kinematics of stars and ionized gas of three early-type spiral galaxies, namely NGC 772, NGC 3898 and NGC 7782. For each galaxy we present a self-consistent Jeans model for the stellar…

We analyze UV observations with FAUST of four sky fields in the general direction of the fourth Galactic quadrant, in which we detect 777 UV sources. This is ~50% more than detected originally by Bowyer et al (1995). We discuss the source…

The high excitation planetary nebula, NGC 6302, has been imaged in two far-ultraviolet (FUV) filters, F169M (Sapphire; {\lambda}$_{\rm eff}$: 1608 {\AA}) and F172M (Silica; {\lambda}$_{\rm eff}$: 1717 {\AA}) and two NUV filters, N219M (B15;…

We present surface photometry for the central regions of a sample of 33 early-type (E, S0, and S0/a) galaxies observed at 1.6 microns (H band) using the Hubble Space Telescope (HST). We employ a new technique of two-dimensional fitting to…

We present Chandra ACIS-I and ACIS-S observations ($\sim$200 ks in total) of the X-ray luminous elliptical galaxy NGC 4636, located in the outskirts of the Virgo cluster. A soft band (0.5-2 keV) image shows the presence of a bright core in…

We have undertaken near-continuous monitoring of the Seyfert 1 galaxy NGC 7469 in the X-ray with RXTE over a ~30d baseline. The source shows strong variability with a root-mean-square (rms) amplitude of ~16 per cent, and peak-to-peak…

Annihilation radiation from supersymmetric particles at the Galactic center could be greatly enhanced if the dark matter density is peaked around the supermassive black hole. Arguments for and against the existence of density spikes are…

We present Sloan g and i imaging from the GMOS instrument on the Gemini North telescope for the globular cluster (GC) system around the Virgo galaxy NGC 4649 (M60). Our three pointings, taken in good seeing conditions, cover an area of…

We have discovered an optically rich galaxy cluster at z=1.7089 with star formation occurring in close proximity to the central galaxy. The system, SpARCS104922.6+564032.5, was detected within the Spitzer Adaptation of the red-sequence…

We present GALEX far-ultraviolet (FUV, $\lambda_{eff}$=1538 \AA) and near-ultraviolet (NUV, $\lambda_{eff}$=2316 \AA) surface photometry of 40 early-type galaxies (ETGs) selected from a wider sample of 65 nearby ETGs showing emission lines…

We present a preliminary analysis of HST-WFPC2 observations of globular cluster systems in the two brightest galaxies, UGC 9799 (cD) and NGC 1129 (non-cD), located in the center of rich clusters.

In this paper we discuss the X-ray point source population of NGC 4472, an elliptical galaxy in the Virgo cluster. We used recent deep Chandra data combined with archival Chandra data to obtain a 380 ks exposure time. We find 238 X-ray…

We present the results of a spectroscopic survey of the outskirts of 4 globular clusters -- NGC 1261, NGC 4590, NGC 1904, and NGC 1851 -- covering targets within 1 degree from the cluster centres, with 2dF/AAOmega on the Anglo-Australian…

The dense central regions of tidally disrupted galaxies can survive as ultra-compact dwarfs (UCDs) that hide among the luminous globular clusters (GCs) in the halo of massive galaxies. An exciting confirmation of this model is the detection…

As part of a large HST project to study the formation and evolution of rich star clusters in the Large Magellanic Cloud, we present results for the Galactic bulge metal-rich globular cluster NGC6553. HST observations using WFPC2, NICMOS and…

We present multi-epoch, $R-$band imaging obtained from the Palomar Transient Factory of a small, fan-shaped reflection nebula in NGC 1333 that experiences prominent brightness fluctuations. Photometry of HBC 340 (K7e) and HBC 341 (M5e), a…